This program will develop methodology and facilities to produce rhesus monkeys free from specified pathogens that interfere with use of the animals in research, have a deleterious effect on the animals' health, or are a significant threat to the health of personnel in contact with the animals. Specific aims are to develop a colony of approximately 100 breeder females and 17 breeder males that will produce offspring free from (1) Herpes B Virus (virus and antibody). (2) Simian Immundeficiency virus (virus and antibody). (3) simian retrovirus (virus and antibody). This includes SRV-1, SRV-2, and STLV-1. (4) Shigella and Salmonella species. (5) Internal (helminths) and external parasites. (6) The sixth specific aim would be to provide an environment that promotes the pyschologic and physical well being of the animals, efficient reproduction and complete animal record documentation. Sub-adult rhesus monkeys will be procurred from the Peoples Republic of China (PRC), be isolated and undergo repeated screenings for specific pathogens (or antibodies). Animals found to be positive by viral isolation or by serology (viral) would be removed. Animals positive for bacterial or parasitic entities would be treated with appropriate regimens and retested. A "shower-in" semi-barrier facility would be used to protect the animals during the latter portion of the screening period and during the entire period following selection as breeders. The operation would be located on an isolated portion of the Texas Primate Center (TPC) premises (approximately 700 feet) from the nearest primate facility. The TPC is located on 208 acres of land 35 miles west of Corpus Christi, Texas.